Glen Canyon Species Status Report
Amphibians and Reptiles
Historic Summary
by
Christina Rinderle
David L.Wegner
Ecosystem Management International, Inc.
for the
Glen canyon institute
1.0 introduction
The Glen Canyon region of the Colorado River provided a unique refugium and life
history zone for many species. Situated on the Colorado Plateau, Glen Canyon was
formed by the flowing waters of the Colorado River downcutting through the
sedimentary rocks formed by millions of years of deposition. The resulting geologic and
ecologic environments defined the living Glen Canyon. While composed of rock, the
side canyons and mainstem river corridor provided unique refugiums where reptiles,
birds, and fish could live, find places to hide from extreme hydrologic events and evolve
into the unique assemblages that were found in the Colorado River system.
This report documents the historic reptiles and amphibians found within the Glen Canyon
environment. These species lend insight into the ecosystem dynamics of Glen Canyon
and throughout the region. Amphibian and Reptile species noted in this report include 6
amphibians and 15 reptiles. These species were all located in Glen Canyon. Today due
to the flooding of Glen Canyon by reservoir Powell, the majorities of these species are
relegated to fragmented locations or have been extirpated from region.
Fragmentation of the Colorado River and Glen Canyon ecosystems by Glen Canyon dam
has separated species, reduced the abilities for natural distribution corridors, and
corrupted the ecological processes that historically defined the Colorado River system.
Today the remaining species are isolated from their historic genetic distribution patterns
with the result eventually leading to species loss. Ecological sustainability requires us to
understand the past before we can begin to reconnect the pieces.
This status report, consolidated from historic studies and data, identify the primary
amphibian and reptile species that were known to frequent the Glen Canyon area. We
have attempted to document the natural history of the species, their habitats, and the
ecological interactions that define their use of the Glen Canyon region.
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2.0 Status summary
Although it is difficult to determine if fluctuations in species number and diversity are
related to human impacts or natural causes, there are several effects that clearly implicate
human populations. Through the creation of Glen Canyon Dam, the canyon itself has
been inundated, altering species by destroying the habitat on which they rely. Threats to
these native species include not only the dam itself, but also several indirect effects. The
first of these is obviously habitat destruction. As the dam prevents natural flooding,
native vegetation such as cottonwood and willow cannot regenerate. Many species rely
on this indigenous habitat for their survival and once this becomes altered or destroyed,
populations are effected. Secondly, once habitats are altered, food sources vary be it
vegetation or species of prey. Finally there is a steady increase in tourism at Reservoir
Powell creating impacts from motorboats, jet skis, and garbage. This environmental and
noise pollution has the potential to greatly effect the species number and diversity in Glen
Canyon. Other non-native threats include the introduction of the bullfrog, Rana
catesbeiana, which is both a predator and competitor for many native species.
Environmentally, increased pollution resulting in acid rain has greatly effected tiger
salamander populations. UV rays have been linked to harm amphibian eggs, and toxins
such as agricultural pesticides and herbicides have aided the decline of many species.
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3.0 Amphibian Species Listing
Amphibians
Ambystoma tigrinum nebulosum Tiger salamander
Bufo punctatus Red-spotted toad
Bufo woodhousei Woodhouse toad, Rocky Mountain toad
Hyla arenicolor Canyon tree frog
Ranapipiens Northern or Western leopard frog
Scaphiopus hammondi Western spadefoot toad
Summary
Several factors have contributed to the decline of amphibian and reptile species diversity
and population size. Glen Canyon Dam has created a large impact in the habitat and
species that historically utilized the Glen Canyon area. All of the species listed in this
report historically relied on Glen Canyon and its surrounding habitat for their survival.
Today many of these species are spatially separated from their historic population bases
and as a result may not be achieving adequate genetic distribution. It is critical to
continue to monitor these species as indicators of the health of this remarkable area.
3.1 Ambystoma tigrinum nebulosum Arizona Tiger salamander
The Arizona Tiger Salamander (Ambystoma tigrinum nebulosum) has a dark black or
gray background with light yellow markings in the form of mottled spots or bars. Some
specimens in small populations may look similar to the Gray Tiger Salamander with the
black dots on the dark gray background. The Arizona Tiger Salamander is found
throughout western Colorado and New Mexico, southeast to northwestern Arizona, and
much of Utah, (see yellow area in distribution map below)
Glen Canyon ecological studies site specimens taken from mile 30 on the San Juan River,
and several specimens taken from Navajo country.
Adult& Juvenile
To protect themselves from the hot summer sun, the Tiger Salamander finds shelter in
decomposing logs, under rocks and in burrows made by mammals. The salamander
comes out of its shelter only when temperatures are cool, for example, at night or after a
rainstorm. The life span of the Arizona salamander can reach as long as twenty years.
Reproduction and Spawning
Mating activity occurs underwater, where females lay eggs two days after picking up the
male's sperm. The female Tiger Salamander attaches her eggs to vegetation about 2-
25cm under the water's surface. After two to four weeks the eggs hatch and the larvae
stay hidden in weeds near the top of the pond. It takes three or four months for the larvae
of the Tiger Salamander to grow into adults.
Diet
Adult, metamorphosed salamanders eat earthworms, and snails, bugs and larval stages of
insects. Larvae feed on aquatic invertebrates and insect larvae, zooplankton, tadpoles and
other larvae.
Biotic interactions
Trout readily consume and deplete larval populations, and the two species are only found
to coexist where vegetated shallows provide habitat inaccessible to trout. Known
predators also include the raccoon, aquatic turtles, western terrestrial garter snake,
bullfrog, bass, American white pelican, ring-billed gull, black-crowned night heron,
green heron, snowy egret, American kestrel, ducks, common raven, crayfish, and giant
water bug. Larval populations can also be affected indirectly by grazing livestock, where
bacterial infections are caused by fecal contamination.
Jundt
Arizona
Barred
Blotched
California
Eastern
Gray
Sonora
Tiger Salamander
Ambystoma tigrinum
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3.2 Bufo punctatus Red-spotted toad
The Red-Spotted Toad is a smaller toad reaching lengths around 2 1/2 to 3 inches. They
have a general body pattern that is flattened, allowing them to crawl beneath rocks and
crevices where they spend much of their time during the day since they are mostly
nocturnal. Additionally, this toad also burrows. Their dorsal coloration ranges from
various shades of brown to gray with scattered red spots. The parotid gland is generally
round and equal to or smaller than the diameter of the eye in size.
They are found from extreme southeastern California east to central Texas and north to
the southern part of Utah to Kansas at elevations of less than 6000'. These toads
generally inhabit drier areas, but need a reliable source of water. They are common in
desert canyons or in semi-arid regions with springs and rain pools. This toad is nocturnal,
but may be diurnal during the breeding season.
According to the Glen Canyon ecological studies, the red spotted toad was common
throughout the Glen Canyon area, primarily utilizing small streams and temporary pools
as its habitat. This species can survive drought conditions by living underground and re-appearing
after storms when water is available.
Adult& Juvenile
Glen Canyon ecological studies notes adults at Ticaboo Creek mouth and side canyon
river mile 140.5; adults common in side canyon with large rocks and water pockets at
mile 140.5, adults at Hidden Passage canyon at mile 76.1, immature adults from Aztec
Canyon to Rainbow Bridge; adults at side canyon, river mile 44.4 and mouth of Warm
Creek, Specimens noted at the mouths of Rock Creek.
Reproduction and Spawning
The red-spotted toad breeds from March to September during or after rains in springs,
rain pools, and temporary pools of intermittent streams, often bounded by large rocks.
Eggs are laid singly, in short strings with sticky jelly around, sometimes as loose, flat
clusters on the bottom of ponds. The eggs hatch in three days and the tadpoles transform
in about 40 - 60 days. Glen Canyon ecological studies noted larvae abundant Trachyte
Creek mouth; tadpoles in side canyon at river mile 44.4 and mouth of Warm Creek
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Diet
Larvae eat suspended matter, algae, plant tissue and organic debris.
Adults consume a variety of terrestrial arthropods such as bugs, and beetles.
Biotic interactions
Predators include birds and mammals; in many instances spadefoot larvae consumes red-spotted
toad larvae through predation.
3.3 Bufo woodhousei Woodhouse toad, Rocky Mountain toad
Adult & Juvenile
The Woodhouse's Toad is a fairly large toad attaining lengths greater than 4 inches. They
usually have a light line running middorsally down their back. The belly of the
Woodhouse's Toad is usually white. Occasionally there may be some other coloration.
There is much variability found within the Woodhouse's Toad; within the same area, they
usually look the same, but across the country or even a state they can look quite different.
The range extends from southeast Montana down through the Great Plains west to Utah ,
and eastern New Mexico. Woodhouse toads are generally found below 7,000 feet in
elevation in wooded bottomlands, mountain canyons, riverbanks, marshes, irrigated
farmland, gardens and residential areas, (see the dark blue region on the map below)
Like most toads, it is predominantly nocturnal and burrows underground or hides under
rocks and plants when inactive. It is active during the wet and dry weather.
Stream and pond habitat about 5 mi up Ticaboo Canyon from mile 149 in Glen Canyon;
lower Kane Creek, mile 40.6; specimens by the river in willow habitat at mile 162;
specimens at mouth of Rock Creek and on San Juan River at mile 20; Warm Springs
Creek at mile 136.6; many specimens from Navajo Country
Reproduction and Spawning
The Woodhouse Toad breeds in ponds, lakes, reservoirs, flooded areas and other bodies
of water lacking a strong current. The eggs are pigmented and laid in two long
intertwined strands of up to 25,000 eggs and attached to submerged vegetation or debris.
Eggs hatch after about 3 days, followed by the larval period, which lasts about 4-7 weeks.
Bufo woodkousii
Toads
Fowler's
Woodhouse's
Southwestern
Jundt
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The life span of the Woodhouse's Toad is unknown. Glen Canyon Ecological Studies
noted larvae in stream and pond habitat about 5 mi up Ticaboo Canyon from mile 149 in
Glen Canyon
Diet
Tadpoles eat organic debris, algae, suspended matter and plant tissue. Adult toads eat
isopods, scorpions, mites, spiders, grasshoppers, crickets, moths, caterpillars, flies,
maggots, bugs, and especially, bees, ants and beetles.
Biotic interactions
Predators include raccoons, skunks, snakes (western hognose snake, northern water
snake, bullsnake, and garter snakes), bullfrog, herons and fish (eat the tadpoles). Larvae
are often consumed by spadefoot toad larvae, insects, and garter and water snakes.
3.4 Hyla arenicolor Canyon tree frog
Adult& Juvenile
Although rather small (1 1/4- 2 1/4 inches long), the Canyon Tree Frog is plump and
toad-like in appearance. It has a well-developed toe pads. The webbing on the hind foot
does not extend to the tip of the fifth toe. The Canyon Tree Frog is normally gray to
brown color on the dorsal surface, with darker spots or blotches on the back. Some
individuals, particularly in Southwest Utah, have no spots. The skin is rather rough. The
ventral surface is cream colored with a yellow or orange tinge on the hind legs. A dark
edged light spot beneath the eye is a field identification. There is no eye stripe. Adult
males have a dusky throat.
The Canyon Tree Frog is found in rocky canyons in arid areas, usually within jumping
distance of perennial and intermittent streams. It prefers streams with a hard rocky
bottom. In the Intermountain Region, it is found only in Southern Utah. The Canyon
Tree frog is predominantly nocturnal and when inactive retreats to rocks or stony
crevices. It is largely a ground dwelling species but occasionally climbs trees.
Distribution is shown on the map below. The Canyon tree frog can be found in all
tributary creeks entering Glen Canyon.
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CANYON TREE FROG
Hylo arenicolor
Bright orange-yellow color on the backs of the thighs is exposed when the frog leaps, a
mechanism for startling or confusing the predator. Immatures and adults have been
observed at Bridge Canyon, Utah; specimens at mouth of Rock Creek, San Juan River at
miles 35 and 20, and Long canyon at mile 95.5
Reproduction and Spawning
The Canyon Tree Frog normally breeds from March to July and possibly as late as
August. Breeding maybe delayed during periods of inadequate rainfall. The frog usually
lays its eggs in rock bound pools along canyon bottoms. The pigmented eggs are
generally attached to objects at the bottom of these pools.
Eggs and tadpoles were observed at Bridge Canyon, Utah.
Diet
Metamorphosed adults feed on caterpillars, beetles, ants, bugs, caddisflies, centipedes,
spiders, and worms. Like most amphibian species, the larvae feed on algae, plant tissue
and suspended organic debris.
Biotic interactions
Predators, although not well known, most likely include various mammals, snakes, and
birds.
3.5 Rana pipiens Northern or Western leopard frog
Adult& Juvenile
The Western leopard frog is common throughout the region.Glen Canyon ecological
studies note specimens in Bridge Canyon, and Navajo Country, also below the mouth of
Ticaboo Creek at mile 148, and a side stream at mile 109. Observations in Lower
Trachyte Creek, in a pool in side canyon at river mile 101.5, Long canyon, pond on river
bank at mile 83.3, pools in West Canyon Creek, lower Kane Creek, near mouth of Padre
Creek and Warm Creek.
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Diet
The leopard frog feed on caterpillars, beetles, ants, bugs, caddisflies, centipedes, spiders,
and worms. Like most amphibian species, the larvae feed on algae, plant tissue and
suspended organic debris.
Biotic interactions
Preyed upon by garter snakes, and the common bullfrog.
3.6 Scaphiopus hammondi Western spadefoot toad
Adult& Juvenile
The Western spadefoot toad is almost entirely nocturnal, with most above ground
movement and breeding occurring during rainy nights. It has a plump body, black,
wedge-shaped "spade" on inner side of hind foot. Front toes are slightly webbed. Its
habitat is mountain valleys and floodplains in the southwest.
The Western spadefoot toad occurs in the tributaries of Glen Canyon. Specimens found
on the San Juan at mile 35; and many in Navajo Country.
Reproduction and Spawning
The Western spadefoot toad waits until water temperature is at least 10 degrees Celsius
before egg deposition and enters the water only to breed. Eggs are deposited in irregular
small cluster, about 25-30 centimeters in diameter, attached to vegetation or debris in
shallow temporary pools or sometimes ephemeral streamcourses Egg clusters rarely
number above 42. Eggs are usually hatched within six days. Complete development can
rapidly occur within three weeks, but may last up to 11 weeks depending on water
temperature, water evaporation, and food resources
Diet
Tadpoles feed on planktonic organisms and algae, but are also carnivorous and will
forage on dead vertebrates and invertebrates. Also, spadefoot tadpoles are known to
pursue and eat fairy shrimp. The capability of tadpole cannibalism in this genus
(Scaphiopus) is one of many adaptations that allows for breeding in temporary pools.
Spadefoot toads are more likely to express a carnivorous/cannibalistic phenotype when
reared with multiple broods that include non-siblings/kin.
Biotic interactions
Placement of mosquito fish by mosquito abatement programs in rain pools threatens
some populations. Bullfrogs emigrating into rain pool breeding sites may also pose a
threat.
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4.0 Reptile Species Listing
Reptiles
Chrysemyspicta belli Western painted turtle
Crotaphytus collaris Collared lizard
Gambelia wislizeni wislizeni Long-nosed leopard lizard
Holbrookia maculata approximana....Speckled Earless lizard
Sauromalm obesus multiforaminatus .Glen Canyon chuckwalla
Sceloporus magister cephaloflavus ....Utah spiny lizard
Sceloporus undulatus elongatus Northern plateau lizard
Sceloporus graciosus graciosus Great Basin sagebrush lizard
Ufa stansburiana stamburiana Northern side-blotched liza rd
Phrynosoma douglassi hernandesi Mountain short-horned lizard
Xantusia vigilis utahensis Utah night lizard
Cnemidophorus tigris septentrionalis..Western whiptail
Cnemidophorus sacki innotatus Plateau whiptail
Thamnophis cyrtopsis cyrtopsis Western black-necked garter snake
Thamnophis elegans vagrans Wandering garter snake
4.1 Chrysemys picta belli Western painted turtle
Adult& Juvenile
The painted turtle has a somewhat flattened, hard shell that is orange or reddish
underneath. Yellow lines are seen on the head and limbs, and the upper jaw is notched at
the tip. Habitat typically includes permanent ponds, reservoirs, marshes, river
backwaters, and the slowest moving portions of streams. These turtles rarely move far
from permanent water, but sometimes colonize nearby seasonally flooded areas before
returning to permanent water sources.
Juvenile painted turtles are more sedentary compared to adults, who move throughout
their inhabited ponds or roam several kilometers along stream or river segments.
Specimens have been taken near a pool at the mouth of Rock Creek, mile 55.6, 3200'.
Additional species were taken at Face Canyon, mile 44.4, and Labyrinth Canyon.
Reproduction and Spawning
Mating usually occurs in the spring, but can also take place in summer and fall. Clutch
and egg size increases with females' body size, and sex is determined by incubation
temperature (temps above 30°C yield only females; temps at about 21-23°C yield only
males). When temperature is consistently below 20°C, eggs fail to hatch.
Diet
Painted turtles obtain food from a variety of aquatic sources such as living and dead
plants, including bryozoans, worms, leeches, insects at all life stages, water mites,
spiders, crustaceans, snails, clams, and fishes. Juveniles feed typically on crustacean
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zooplankton. It has been noted that the amount of plant material in a diet may increase
with the turtle's size.
Biotic interactions
Raccoons and skunks frequently eat the turtle eggs, sometimes within 24 hrs of the eggs
being deposited in nests. Other predators include herons, watersnakes, racers, and
bullfrogs. Interestingly, largemouth bass and other often predatory fishes avoid painted
turtles, possibly because of the turtles clawing and biting capabilities. Other notes are
that these turtles are sometimes infested with leeches and also females are sensitive to
nest disturbances.
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Adult& Juvenile
The collared lizard can be recognized by its large and sometimes bright yellow head. It
has a long tail and two areas of black colorization resembling an incomplete collar around
the neck. Body color varies from turquoise to greenish to brown and adults are covered
with numerous small light spots. The lizard is located throughout the western and south-central
U.S., from eastern Utah, Colorado, Kansas, and Missouri, south through Arizona,
New Mexico, Oklahoma, Arkansas, and Texas, to northern Mexico. Habitat includes
rocky canyons, slopes, and gullies, rocky ledges above cliffs, exposures of bedrock, and
areas with scattered large rocks and sparse vegetation.
Adult males tend to be aggressive and territorial towards other males, especially during
breeding season when females are present. Younger males avoid adult males whenever
possible.
Reproduction and Spawning
Reproductive females develop orange spots on their sides that vary in brightness
depending on the females' ovulation stage. Mating takes place in the spring with
copulation occurring a day or two prior to bright coloration. Eggs hatch about 7-13
weeks after oviposition and growth is rapid.
Diet
Beetles and grasshoppers comprise the majority of the diet, along with arthropods and
small lizards, however, collared lizards are opportunistic feeders and their diets change
based on availability. Juveniles eat small insects and spiders
Biotic interactions
The list of predators includes diurnal raptors and snakes. Although perching in the open
would make them an easy target, collard lizards continue to do so with lack of concern.
4.2 Crotaphytus collaris Collared lizard
4.3 Gambelia wislizeni wislizeni Long-nosed leopard liza rd
Adult/ Juvenile
The leopard lizard can be distinguished by its light brownish-gray body with numerous
small brown spots. Female has red-orange spots that occur on her sides during the
breeding season. Leopard lizard can be found in Oregon, southern Idaho south through
southern and eastern California, Nevada, Utah, western Colorado, Arizona, New Mexico,
and western Texas to northern Mexico.
Leopard Lizards can be most commonly found on sparsely vegetated, flat or gently
sloping shrublands, consisting of greasewood and sagebrush, in or near the mouths of
canyons. Lizards may use rodent or other burrows to seek refuge at nighttime and during
the winter months.
Reproduction
Mating occurs in the spring and eggs are laid underground in their burrows. Hatchlings
appear by the end of the summer and reach maturity in 1-2 yrs.
Diet
Long-nosed leopard lizard diet is dominated by grasshoppers, but also consists of beetles,
spiders, wasps, ant lions, caterpillars, and lizards such as the western whiptail, side-blotched
lizard, and plateau lizard.
Biotic Interactions
Predators include various raptors, carnivorous mammals, and large snakes.
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Other Common Names: Speckled Earless Lizard, Lesser Earless Lizard
Adult/Juvenile
They are found in southwestern Utah and Colorado, southern South Dakota, eastern
Wyoming south through Nebraska, Kansas, Oklahoma, Arizona, New Mexico, and Texas
to central Mexico. Body 41/2 inches long, short, and somewhat flattened. During
breeding season, reproductive females have an orange-yellow of their throat and sides of
the body. Dry, rocky or sandy areas along streams, and flat areas with sparse vegetation;
lower Sonoran- Transition life zones. The lizard buries itself underground during hot and
cold temperature extremes.
Reproduction
6-8 eggs laid early July -August, hatchlings appear August to September
Diet
Earless lizard is an opportunist, feeding on various small invertebrates such as
grasshoppers, bugs, ants, Lepidoptera, beetles, and spiders.
4.4 Holbrookia maculata approximana ..Speckled Earless lizard
Biotic Interactions
Predators include owls, the long-nosed leopard lizard, hog-nosed snake, racer, bullsnake,
milk snake, western rattlesnake, various hawks and carnivorous mammals, including the
northern grasshopper mouse (Onychomys leucogaster)
4.5 Sauromalus obesus multiforaminatus Glen Canyon chuckwalla
Adult/ Juvenile
Glen Canyon subspecies of chuckwalla is found only in the Colorado River gorge
between Garfield County, Utah and Page County, Arizona. The Glen Canyon
chuckwalla is listed on the species of special concern list due to its population and habitat
decline. It is a rock-dwelling lizard that occurs around the Colorado River from the Glen
Canyon Dam area to near Kite and the Henry Mountains of southeastern Utah.
Characteristics include its thick tail with its blunt tip; it has nasal salt-secreting glands
that are effective in eliminating salts with minimal water loss. This diurnal lizard
emerges in the morning and, before seeking food, basks hi the sun until its optimum body
temperature of 100 ° F. is reached.
Reproduction
Females lay six to ten white soft-shelled eggs during the summer months
Diet
This desert lizard is primarily vegetarian (unlike other reptiles in the region), and eats
fruit, leaves, buds and flowers.
Biotic Interactions
Biotic Interactions are unavailable for this species.
4.6 Sceloporus magister cephaloflavus ....Utah spiny lizard
Adult/ Juvenile
Dorsum with large spiny scales, often scattered yellowish scales on the sides; head
yellowish to orange in adult; male: blue patch at center of the throat, vivid black-edged
blue or green patch on each side of the belly, large black mark on each side of the neck;
females: blue areas faint or absent; found in central California, southern Utah,
southwestern Colorado south through Arizona, New Mexico, and western Texas to
northeastern Baja California and north-central mainland Mexico. Habitat includes shrub-covered
dirt banks and sparsely vegetated rocky areas near flowing streams.
Adults remain in a relatively small home range that is fairly constant year to year in
contrast to juveniles who move several hundred meters before establishing a home range.
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Reproduction
Mating takes place in the spring, clutch size is 2-8 and 2 clutches a year are produced in
southern Utah; hatchlings appear in early Aug in southern Utah and occur most often on
the ground.
Diet
Feed opportunistically on available arthropods, occasional small lizards such as the
western whiptail, and some plant material.
Biotic Interactions
Perch on large rocks, shrubs, or trees such as cottonwoods. They prefer soft soils under
greasewood, rabbit brush, or salt-cedar. Predators include various birds that pluck them
from their perches, collared lizard, and long-nosed leopard lizard.
4.7 Scelopoms undulatus elongatus Northern plateau lizard
Adult/Juvenile
Found in rocky areas throughout eastern Utah, western Colorado, southwestern and
south-central Wyoming, and south into northern Arizona and north-western New Mexico.
Blue patches on sides of throat don't usually meet at midline; lips and chin never orange
or yellow in color, dark crossbands on back often faint, discontinuous or absent, dark
lateral stripe usually present on adult male.
Reproduction
Mating occurs in the spring
Diet
Eats whatever small arthropods are available, ants, beetles and grasshoppers dominate
their diet.
Biotic Interactions
Taxa elongates and tristichus intergrade in southwestern Utah.
4.8 Sceloporus graciosus graciosus Great Basin sagebrush lizard
Adult/Juvenile
Dorsum has small, spiny scales, usually with a pale dorsal-lateral stripe on each side; rear
thigh scales are small, often granular and unkeeled; throat may be blue-mottled, but not
distinct; supra ocular scales separated from median head scales by complete rows of
small scales. Max size is 15cm TL. Distribution: Washington, Idaho, Montana, and
western north Dakota south to northern Baja California, central Arizona, and
northwestern New Mexico. Habitat includes pinon-juniper, semi-desert shrubland
(including saltbush, sagebrush), montane woodlands.
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Reproduction- in So Utah: courtship begins in May ; most females produce 2 clutches/yr
and average 4 eggs, laid in June and July; Hatchlings appear early to mid August.
Survival is 12-66% for egg-to-yearling stage, 40-50% for yearlings, and 40-70% for
adults. In Utah 3A of hatchlings don't survive their first year.
Diet
Ants most important food source, other food includes, grasshoppers, flies, beetles,
spiders, mites and pseudoscorpions.
Biotic Interactions
The sagebrush lizard perches on junipers and other plants, usually near the ground, but up
to heights of 1-2 m. Temp extremes are spent under rocks or in rodent burrows.
Predators include assortment of mammals, birds, and reptiles, noted cases include striped
whipsnake, plateau lizard, American kestrels, and ash-throated flycatcher.
4.9 Ufa stansburiana stansburiana Northern side-blotched lizard
Adult/Juvenile
Dorsum uniform color or w/ numerous small light and dark dots, scales along the middle
of back are uniform size; dark blotch on the sides of chest, throat often blue with orange
rim; a large % of adults have either broken or regenerated tails. Distribution: south-central
Washington, southeastern Idaho, western Colorado, southwestern Oklahoma,
south through Oregon, California, Nevada, Arizona, New Mexico, and Texas to southern
Baja California, and northwestern and north-central mainland Mexico. Abundance
increases with amt of precipitation from previous year.
It's found in washes, boulder-strewn ravines, rocky canyon slopes, bedrock exposures,
rimrock outcroppings, rocky cliff bases, and flat, shrubby areas in canyon bottoms with
soft, deep soils. Open pinon-juniper, semidesert shrubland, patchy stream-side
vegetation. Burrow underground in winter.
Reproduction
Courtship begins in the spring following the emergence form hibernation; females may
store and use sperm for up to several months after mating. One clutch/season, hatchlings
emerge in August.
Diet
Opportunistic foragers; include grasshoppers, beetles, leafhoppers, and other bugs, ants,
various insect larvae, and spiders. Cannibalism occasionally occurs (noted that adult
males had eaten juveniles).
Biotic Interactions
Predators include striped whipsnake and especially the leopard lizard, also potential from
reptiles, birds, mammals, and invertebrates such as spiders and scorpions.
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4.10 Phrynosoma douglassi hernandesi... Mountain short-horned lizard
Adult/Juvenile
Body wide and flattened, spines at back of the head are the same length as width at the
base, one row of enlarged scales fringing each side of the body. Dorsal color orientation
blends cryptically with soil. 30-33mm TL in Utah; distribution: southern Alberta and
Saskatchewan south through Montana, Wyoming, the western Dakotas, eastern Nevada,
Utah, Colorado, western Nebraska, Arizona, New Mexico, and western Texas to south-central
Mexico. Habitat varies from short-grass prairie, sagebrush, semidesert shrubland,
shale barrens, pinon-juniper, pine-oak, oak-grass, open conifer forests. Note: movement
patterns poorly known, but in Utah a juvenile displaced 400m from its capture location
returned to that site after 280 days.
Reproduction
Mating in the spring, some females may be unreceptive to males after mating, others
mate more than once in a few-day period. This species does not lay eggs, rather it gives
birth to live young (eggs develop inside the female during spring and summer -gestation
is about 3 months). Neonates quickly shed their sacs and begin feeding after 1-2 hrs from
birth.
Diet
Ants dominate the diet, also eat miscellaneous other insects and spiders, also beetles and
small grasshoppers.
Biotic Interactions
Little predation info avail; striped whipsnake and burrowing owl
4.11 Xantusia vigilis utahensis Utah night lizard
Adult/Juvenile
The Utah night lizard is listed as a species of special concern due to its specialized habitat
within the Glen Canyon region. It occurs under and among rocks or fallen plant material
(e.g. yucca) from Henry Mountains and Natural Bridges National Monument (east of the
Colorado River) south to the San Juan River. The Utah Night lizard has lidless eyes and
vertical pupils.
Reproduction
Night lizards give birth to live young. They mate in early summer, usually May or June,
and 1 to 3 young are born, tail first, a few months later.
Diet
It frequents yucca plants and agaves and feeds on termites, ants, beetles and flies, which
it finds among vegetation or rocks.
15
Biotic Interactions
Biotic Interactions are unavailable for this species.
4.12 Cnemidophorus tigris septentrionalis Western whiptail
Adult/Juvenile
Body long and slender, dorsum with small granular scales, belly with larger rectangular
scales, unmarked or with black marks on the front edge of some; dorsum with light
stripes, dark fields broken into separate bars or spots; throat may be pinkish or orangish
in adults; distribution: eastern Oregon and southern Idaho, south through California,
Nevada, Utah, western Colorado, Arizona and New Mexico, and western Texas to
southern Baja California and northwestern and north-central Mexico.
Larger individuals spend more time in the shade than juveniles despite similar thermal
preferences and tolerances.
Lowland river valleys, canyon bottoms to adjacent low mesa tops; openly spaced shrubs
(greasewood, sagebrush, rabbit brush) or pinon pine; areas along rivers with patchy
shrubs and scattered cottonwood trees; winter spent in rodent or self-dug burrows.
Reproduction
Mating from late May to mid June; male and female form temporary monogamous pairs;
hatchlings appear in September; clutch size and growth rates increase with arthropod
abundance associated with higher precipitation levels
Diet
They feed opportunistically on arthropods, specifically those found in plant litter at the
base of perennial plants. Probe leaf litter and climb into plants to get prey. Odors sensed
by the tongue help reveal potential prey. Diet includes beetles, grasshoppers, insect
larvae, termites, ants, and sometimes scorpions and side-blotched lizards. Also predation
on small Sceloporus lizards.
Biotic Interactions
Predators include roadrunners, hawks, collared lizards, leopard lizards, whip snakes, and
racers, long-nosed leopard lizard.
4.13 Cnemidophorus sacki innotatus Plateau whiptail
Adult/ Juvenile
Body long and slender, dorsum with small granular scales, belly with large rectangular
scales, dorsum and sides with six or seven light stripes, dark fields between the stripes are
interrupted by light areas; tail blue (pale in adult; bright in juvenile)
Distribution: southern Utah, western Colorado, northern and central Arizona, and
northern and central New Mexico.
16
Habitat includes pinon juniper, sagebrush, semi-desert and mountain shrublands, lowland
riparian zones, encompassing rocky slopes and deep sandy soils in flat areas. Ground-dwelling.
Reproduction
Species consists only of females and reproduces by parthenogenesis. Eggs are laid
around June and hatchlings appear mid- to late August.
Diet
Opportunistic feeders -arthropods found on the ground or shallowly buried; includes
spiders, caterpillars, grasshoppers, crickets, adult and larval beetles, aphids, leafhoppers
and other insects; ants eaten infrequently;
Biotic interactions: predators include various birds, reptiles, and mammals
4.14 Thamnophis cyrtopsis cyrtopsis Western black-necked garter snake
Adult/Juvenile
Aquatic snake; Sees well in the air, but poor underwater vision; moderately fragile tail
that breaks between rather within the vertebrae and doesn't significantly regenerate.
Biotic interactions
Prey on amphibians in temporary pools in both lowland and upland areas; native stream
associated spp include red-spotted toad, plains leopard frog, black-necked garter snake,
and plains garter snake. Black-necked garter snake sometimes preys on Woodhouse
toads. Garters are preyed upon by racers
4.15 Thamnophis elegans vagrani Wandering garter snake
Adult/Juvenile
Aquatic snake; Sees well in the air, but poor underwater vision; moderately fragile tail
that breaks between rather within the vertebrae and doesn't significantly regenerate.
Biotic interactions
Prey on amphibians in temporary pools in both lowland and upland areas; native stream
associated spp include red-spotted toad, plains leopard frog, black-necked garter snake,
and plains garter snake.
5.0 Summary
Several factors have contributed to the decline of amphibian and reptile species diversity
and population size. By far, Glen Canyon Dam has created a large impact in the habitat
and species associated. All of the species listed in this report currently rely on Glen
Canyon and its surrounding habitat for their survival. It is critical to continue to monitor
these species as indicators of the health of this remarkable area.
17
6.0 Literature Cited
Bernard, Stephen R. and Kenneth R. Brown. U.S. Department of the Interior - Bureau of
Land Management Technical Note. "Distribution of Mammals, Reptiles, and
Amphibians by BLM Physiographic Regions and A.W. Keuchler's Associations
for the Eleven Western States." Issued August 1977, Revised July 1978.
Collins, Henry Hill, Jr. Complete Field Guide to American Wildlife. New York: Harper
& Brothers Publishers, 1959.
Hammerson, Geoffrey A. Amphibians and Reptiles Field Guide, Second Edition. Niwot,
Colorado: University Press of Colorado & Colorado Division of Wildlife, 1999.
Tanner, Wilmer W. "1975 Checklist of Utah Amphibians and Reptiles." Provo, Utah:
Brigham Young University, 1975.
University of Utah, "Endemic Amphibians and Reptiles of the Colorado River System: A
Status Report."
Utah Division of Wildlife Resources. Amphibian and Reptile Distribution Maps,
Latilong Distribution, 1979.
Woodbury, Angus M. and the staff of the Division of Biological Sciences. Working Plan
for Ecological Studies as Part of the Upper Colorado Basin Salvage Program.
National Park Service and University of Utah, 1957.
Woodbury, Angus M. University of Utah Anthropological Papers. "Ecological Studies
of the Flora and Fauna in Glen Canyon." University of Utah Press, 1959.
Woodbury, Angus M. University of Utah Biological Series, Volume 1 Number 4. "A
Descriptive Catalog of the Reptiles of Utah." University of Utah Press, 1958.
Woodbury, Angus M. University of Utah Biological Series, Volume 1 Number 31.
"Biological Resources of Glen Canyon Reservoir." University of Utah Press,
1958.
Woodbury, Angus M. Working Plan for Ecological Studies. University of Utah Press,
1957.
World Wide Web, Accessed Division of Fish and Wildlife, Department of Natural
Resources, Bureau of Land Management, and National Park Service websites,
2000.
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Glen Canyon Species Status Report
Amphibians and Reptiles
Historic Summary
by
Christina Rinderle
David L.Wegner
Ecosystem Management International, Inc.
for the
Glen canyon institute
1.0 introduction
The Glen Canyon region of the Colorado River provided a unique refugium and life
history zone for many species. Situated on the Colorado Plateau, Glen Canyon was
formed by the flowing waters of the Colorado River downcutting through the
sedimentary rocks formed by millions of years of deposition. The resulting geologic and
ecologic environments defined the living Glen Canyon. While composed of rock, the
side canyons and mainstem river corridor provided unique refugiums where reptiles,
birds, and fish could live, find places to hide from extreme hydrologic events and evolve
into the unique assemblages that were found in the Colorado River system.
This report documents the historic reptiles and amphibians found within the Glen Canyon
environment. These species lend insight into the ecosystem dynamics of Glen Canyon
and throughout the region. Amphibian and Reptile species noted in this report include 6
amphibians and 15 reptiles. These species were all located in Glen Canyon. Today due
to the flooding of Glen Canyon by reservoir Powell, the majorities of these species are
relegated to fragmented locations or have been extirpated from region.
Fragmentation of the Colorado River and Glen Canyon ecosystems by Glen Canyon dam
has separated species, reduced the abilities for natural distribution corridors, and
corrupted the ecological processes that historically defined the Colorado River system.
Today the remaining species are isolated from their historic genetic distribution patterns
with the result eventually leading to species loss. Ecological sustainability requires us to
understand the past before we can begin to reconnect the pieces.
This status report, consolidated from historic studies and data, identify the primary
amphibian and reptile species that were known to frequent the Glen Canyon area. We
have attempted to document the natural history of the species, their habitats, and the
ecological interactions that define their use of the Glen Canyon region.
1
2.0 Status summary
Although it is difficult to determine if fluctuations in species number and diversity are
related to human impacts or natural causes, there are several effects that clearly implicate
human populations. Through the creation of Glen Canyon Dam, the canyon itself has
been inundated, altering species by destroying the habitat on which they rely. Threats to
these native species include not only the dam itself, but also several indirect effects. The
first of these is obviously habitat destruction. As the dam prevents natural flooding,
native vegetation such as cottonwood and willow cannot regenerate. Many species rely
on this indigenous habitat for their survival and once this becomes altered or destroyed,
populations are effected. Secondly, once habitats are altered, food sources vary be it
vegetation or species of prey. Finally there is a steady increase in tourism at Reservoir
Powell creating impacts from motorboats, jet skis, and garbage. This environmental and
noise pollution has the potential to greatly effect the species number and diversity in Glen
Canyon. Other non-native threats include the introduction of the bullfrog, Rana
catesbeiana, which is both a predator and competitor for many native species.
Environmentally, increased pollution resulting in acid rain has greatly effected tiger
salamander populations. UV rays have been linked to harm amphibian eggs, and toxins
such as agricultural pesticides and herbicides have aided the decline of many species.
2
3.0 Amphibian Species Listing
Amphibians
Ambystoma tigrinum nebulosum Tiger salamander
Bufo punctatus Red-spotted toad
Bufo woodhousei Woodhouse toad, Rocky Mountain toad
Hyla arenicolor Canyon tree frog
Ranapipiens Northern or Western leopard frog
Scaphiopus hammondi Western spadefoot toad
Summary
Several factors have contributed to the decline of amphibian and reptile species diversity
and population size. Glen Canyon Dam has created a large impact in the habitat and
species that historically utilized the Glen Canyon area. All of the species listed in this
report historically relied on Glen Canyon and its surrounding habitat for their survival.
Today many of these species are spatially separated from their historic population bases
and as a result may not be achieving adequate genetic distribution. It is critical to
continue to monitor these species as indicators of the health of this remarkable area.
3.1 Ambystoma tigrinum nebulosum Arizona Tiger salamander
The Arizona Tiger Salamander (Ambystoma tigrinum nebulosum) has a dark black or
gray background with light yellow markings in the form of mottled spots or bars. Some
specimens in small populations may look similar to the Gray Tiger Salamander with the
black dots on the dark gray background. The Arizona Tiger Salamander is found
throughout western Colorado and New Mexico, southeast to northwestern Arizona, and
much of Utah, (see yellow area in distribution map below)
Glen Canyon ecological studies site specimens taken from mile 30 on the San Juan River,
and several specimens taken from Navajo country.
Adult& Juvenile
To protect themselves from the hot summer sun, the Tiger Salamander finds shelter in
decomposing logs, under rocks and in burrows made by mammals. The salamander
comes out of its shelter only when temperatures are cool, for example, at night or after a
rainstorm. The life span of the Arizona salamander can reach as long as twenty years.
Reproduction and Spawning
Mating activity occurs underwater, where females lay eggs two days after picking up the
male's sperm. The female Tiger Salamander attaches her eggs to vegetation about 2-
25cm under the water's surface. After two to four weeks the eggs hatch and the larvae
stay hidden in weeds near the top of the pond. It takes three or four months for the larvae
of the Tiger Salamander to grow into adults.
Diet
Adult, metamorphosed salamanders eat earthworms, and snails, bugs and larval stages of
insects. Larvae feed on aquatic invertebrates and insect larvae, zooplankton, tadpoles and
other larvae.
Biotic interactions
Trout readily consume and deplete larval populations, and the two species are only found
to coexist where vegetated shallows provide habitat inaccessible to trout. Known
predators also include the raccoon, aquatic turtles, western terrestrial garter snake,
bullfrog, bass, American white pelican, ring-billed gull, black-crowned night heron,
green heron, snowy egret, American kestrel, ducks, common raven, crayfish, and giant
water bug. Larval populations can also be affected indirectly by grazing livestock, where
bacterial infections are caused by fecal contamination.
Jundt
Arizona
Barred
Blotched
California
Eastern
Gray
Sonora
Tiger Salamander
Ambystoma tigrinum
3
3.2 Bufo punctatus Red-spotted toad
The Red-Spotted Toad is a smaller toad reaching lengths around 2 1/2 to 3 inches. They
have a general body pattern that is flattened, allowing them to crawl beneath rocks and
crevices where they spend much of their time during the day since they are mostly
nocturnal. Additionally, this toad also burrows. Their dorsal coloration ranges from
various shades of brown to gray with scattered red spots. The parotid gland is generally
round and equal to or smaller than the diameter of the eye in size.
They are found from extreme southeastern California east to central Texas and north to
the southern part of Utah to Kansas at elevations of less than 6000'. These toads
generally inhabit drier areas, but need a reliable source of water. They are common in
desert canyons or in semi-arid regions with springs and rain pools. This toad is nocturnal,
but may be diurnal during the breeding season.
According to the Glen Canyon ecological studies, the red spotted toad was common
throughout the Glen Canyon area, primarily utilizing small streams and temporary pools
as its habitat. This species can survive drought conditions by living underground and re-appearing
after storms when water is available.
Adult& Juvenile
Glen Canyon ecological studies notes adults at Ticaboo Creek mouth and side canyon
river mile 140.5; adults common in side canyon with large rocks and water pockets at
mile 140.5, adults at Hidden Passage canyon at mile 76.1, immature adults from Aztec
Canyon to Rainbow Bridge; adults at side canyon, river mile 44.4 and mouth of Warm
Creek, Specimens noted at the mouths of Rock Creek.
Reproduction and Spawning
The red-spotted toad breeds from March to September during or after rains in springs,
rain pools, and temporary pools of intermittent streams, often bounded by large rocks.
Eggs are laid singly, in short strings with sticky jelly around, sometimes as loose, flat
clusters on the bottom of ponds. The eggs hatch in three days and the tadpoles transform
in about 40 - 60 days. Glen Canyon ecological studies noted larvae abundant Trachyte
Creek mouth; tadpoles in side canyon at river mile 44.4 and mouth of Warm Creek
4
Diet
Larvae eat suspended matter, algae, plant tissue and organic debris.
Adults consume a variety of terrestrial arthropods such as bugs, and beetles.
Biotic interactions
Predators include birds and mammals; in many instances spadefoot larvae consumes red-spotted
toad larvae through predation.
3.3 Bufo woodhousei Woodhouse toad, Rocky Mountain toad
Adult & Juvenile
The Woodhouse's Toad is a fairly large toad attaining lengths greater than 4 inches. They
usually have a light line running middorsally down their back. The belly of the
Woodhouse's Toad is usually white. Occasionally there may be some other coloration.
There is much variability found within the Woodhouse's Toad; within the same area, they
usually look the same, but across the country or even a state they can look quite different.
The range extends from southeast Montana down through the Great Plains west to Utah ,
and eastern New Mexico. Woodhouse toads are generally found below 7,000 feet in
elevation in wooded bottomlands, mountain canyons, riverbanks, marshes, irrigated
farmland, gardens and residential areas, (see the dark blue region on the map below)
Like most toads, it is predominantly nocturnal and burrows underground or hides under
rocks and plants when inactive. It is active during the wet and dry weather.
Stream and pond habitat about 5 mi up Ticaboo Canyon from mile 149 in Glen Canyon;
lower Kane Creek, mile 40.6; specimens by the river in willow habitat at mile 162;
specimens at mouth of Rock Creek and on San Juan River at mile 20; Warm Springs
Creek at mile 136.6; many specimens from Navajo Country
Reproduction and Spawning
The Woodhouse Toad breeds in ponds, lakes, reservoirs, flooded areas and other bodies
of water lacking a strong current. The eggs are pigmented and laid in two long
intertwined strands of up to 25,000 eggs and attached to submerged vegetation or debris.
Eggs hatch after about 3 days, followed by the larval period, which lasts about 4-7 weeks.
Bufo woodkousii
Toads
Fowler's
Woodhouse's
Southwestern
Jundt
5
The life span of the Woodhouse's Toad is unknown. Glen Canyon Ecological Studies
noted larvae in stream and pond habitat about 5 mi up Ticaboo Canyon from mile 149 in
Glen Canyon
Diet
Tadpoles eat organic debris, algae, suspended matter and plant tissue. Adult toads eat
isopods, scorpions, mites, spiders, grasshoppers, crickets, moths, caterpillars, flies,
maggots, bugs, and especially, bees, ants and beetles.
Biotic interactions
Predators include raccoons, skunks, snakes (western hognose snake, northern water
snake, bullsnake, and garter snakes), bullfrog, herons and fish (eat the tadpoles). Larvae
are often consumed by spadefoot toad larvae, insects, and garter and water snakes.
3.4 Hyla arenicolor Canyon tree frog
Adult& Juvenile
Although rather small (1 1/4- 2 1/4 inches long), the Canyon Tree Frog is plump and
toad-like in appearance. It has a well-developed toe pads. The webbing on the hind foot
does not extend to the tip of the fifth toe. The Canyon Tree Frog is normally gray to
brown color on the dorsal surface, with darker spots or blotches on the back. Some
individuals, particularly in Southwest Utah, have no spots. The skin is rather rough. The
ventral surface is cream colored with a yellow or orange tinge on the hind legs. A dark
edged light spot beneath the eye is a field identification. There is no eye stripe. Adult
males have a dusky throat.
The Canyon Tree Frog is found in rocky canyons in arid areas, usually within jumping
distance of perennial and intermittent streams. It prefers streams with a hard rocky
bottom. In the Intermountain Region, it is found only in Southern Utah. The Canyon
Tree frog is predominantly nocturnal and when inactive retreats to rocks or stony
crevices. It is largely a ground dwelling species but occasionally climbs trees.
Distribution is shown on the map below. The Canyon tree frog can be found in all
tributary creeks entering Glen Canyon.
6
CANYON TREE FROG
Hylo arenicolor
Bright orange-yellow color on the backs of the thighs is exposed when the frog leaps, a
mechanism for startling or confusing the predator. Immatures and adults have been
observed at Bridge Canyon, Utah; specimens at mouth of Rock Creek, San Juan River at
miles 35 and 20, and Long canyon at mile 95.5
Reproduction and Spawning
The Canyon Tree Frog normally breeds from March to July and possibly as late as
August. Breeding maybe delayed during periods of inadequate rainfall. The frog usually
lays its eggs in rock bound pools along canyon bottoms. The pigmented eggs are
generally attached to objects at the bottom of these pools.
Eggs and tadpoles were observed at Bridge Canyon, Utah.
Diet
Metamorphosed adults feed on caterpillars, beetles, ants, bugs, caddisflies, centipedes,
spiders, and worms. Like most amphibian species, the larvae feed on algae, plant tissue
and suspended organic debris.
Biotic interactions
Predators, although not well known, most likely include various mammals, snakes, and
birds.
3.5 Rana pipiens Northern or Western leopard frog
Adult& Juvenile
The Western leopard frog is common throughout the region.Glen Canyon ecological
studies note specimens in Bridge Canyon, and Navajo Country, also below the mouth of
Ticaboo Creek at mile 148, and a side stream at mile 109. Observations in Lower
Trachyte Creek, in a pool in side canyon at river mile 101.5, Long canyon, pond on river
bank at mile 83.3, pools in West Canyon Creek, lower Kane Creek, near mouth of Padre
Creek and Warm Creek.
7
Diet
The leopard frog feed on caterpillars, beetles, ants, bugs, caddisflies, centipedes, spiders,
and worms. Like most amphibian species, the larvae feed on algae, plant tissue and
suspended organic debris.
Biotic interactions
Preyed upon by garter snakes, and the common bullfrog.
3.6 Scaphiopus hammondi Western spadefoot toad
Adult& Juvenile
The Western spadefoot toad is almost entirely nocturnal, with most above ground
movement and breeding occurring during rainy nights. It has a plump body, black,
wedge-shaped "spade" on inner side of hind foot. Front toes are slightly webbed. Its
habitat is mountain valleys and floodplains in the southwest.
The Western spadefoot toad occurs in the tributaries of Glen Canyon. Specimens found
on the San Juan at mile 35; and many in Navajo Country.
Reproduction and Spawning
The Western spadefoot toad waits until water temperature is at least 10 degrees Celsius
before egg deposition and enters the water only to breed. Eggs are deposited in irregular
small cluster, about 25-30 centimeters in diameter, attached to vegetation or debris in
shallow temporary pools or sometimes ephemeral streamcourses Egg clusters rarely
number above 42. Eggs are usually hatched within six days. Complete development can
rapidly occur within three weeks, but may last up to 11 weeks depending on water
temperature, water evaporation, and food resources
Diet
Tadpoles feed on planktonic organisms and algae, but are also carnivorous and will
forage on dead vertebrates and invertebrates. Also, spadefoot tadpoles are known to
pursue and eat fairy shrimp. The capability of tadpole cannibalism in this genus
(Scaphiopus) is one of many adaptations that allows for breeding in temporary pools.
Spadefoot toads are more likely to express a carnivorous/cannibalistic phenotype when
reared with multiple broods that include non-siblings/kin.
Biotic interactions
Placement of mosquito fish by mosquito abatement programs in rain pools threatens
some populations. Bullfrogs emigrating into rain pool breeding sites may also pose a
threat.
8
4.0 Reptile Species Listing
Reptiles
Chrysemyspicta belli Western painted turtle
Crotaphytus collaris Collared lizard
Gambelia wislizeni wislizeni Long-nosed leopard lizard
Holbrookia maculata approximana....Speckled Earless lizard
Sauromalm obesus multiforaminatus .Glen Canyon chuckwalla
Sceloporus magister cephaloflavus ....Utah spiny lizard
Sceloporus undulatus elongatus Northern plateau lizard
Sceloporus graciosus graciosus Great Basin sagebrush lizard
Ufa stansburiana stamburiana Northern side-blotched liza rd
Phrynosoma douglassi hernandesi Mountain short-horned lizard
Xantusia vigilis utahensis Utah night lizard
Cnemidophorus tigris septentrionalis..Western whiptail
Cnemidophorus sacki innotatus Plateau whiptail
Thamnophis cyrtopsis cyrtopsis Western black-necked garter snake
Thamnophis elegans vagrans Wandering garter snake
4.1 Chrysemys picta belli Western painted turtle
Adult& Juvenile
The painted turtle has a somewhat flattened, hard shell that is orange or reddish
underneath. Yellow lines are seen on the head and limbs, and the upper jaw is notched at
the tip. Habitat typically includes permanent ponds, reservoirs, marshes, river
backwaters, and the slowest moving portions of streams. These turtles rarely move far
from permanent water, but sometimes colonize nearby seasonally flooded areas before
returning to permanent water sources.
Juvenile painted turtles are more sedentary compared to adults, who move throughout
their inhabited ponds or roam several kilometers along stream or river segments.
Specimens have been taken near a pool at the mouth of Rock Creek, mile 55.6, 3200'.
Additional species were taken at Face Canyon, mile 44.4, and Labyrinth Canyon.
Reproduction and Spawning
Mating usually occurs in the spring, but can also take place in summer and fall. Clutch
and egg size increases with females' body size, and sex is determined by incubation
temperature (temps above 30°C yield only females; temps at about 21-23°C yield only
males). When temperature is consistently below 20°C, eggs fail to hatch.
Diet
Painted turtles obtain food from a variety of aquatic sources such as living and dead
plants, including bryozoans, worms, leeches, insects at all life stages, water mites,
spiders, crustaceans, snails, clams, and fishes. Juveniles feed typically on crustacean
9
zooplankton. It has been noted that the amount of plant material in a diet may increase
with the turtle's size.
Biotic interactions
Raccoons and skunks frequently eat the turtle eggs, sometimes within 24 hrs of the eggs
being deposited in nests. Other predators include herons, watersnakes, racers, and
bullfrogs. Interestingly, largemouth bass and other often predatory fishes avoid painted
turtles, possibly because of the turtles clawing and biting capabilities. Other notes are
that these turtles are sometimes infested with leeches and also females are sensitive to
nest disturbances.
10
Adult& Juvenile
The collared lizard can be recognized by its large and sometimes bright yellow head. It
has a long tail and two areas of black colorization resembling an incomplete collar around
the neck. Body color varies from turquoise to greenish to brown and adults are covered
with numerous small light spots. The lizard is located throughout the western and south-central
U.S., from eastern Utah, Colorado, Kansas, and Missouri, south through Arizona,
New Mexico, Oklahoma, Arkansas, and Texas, to northern Mexico. Habitat includes
rocky canyons, slopes, and gullies, rocky ledges above cliffs, exposures of bedrock, and
areas with scattered large rocks and sparse vegetation.
Adult males tend to be aggressive and territorial towards other males, especially during
breeding season when females are present. Younger males avoid adult males whenever
possible.
Reproduction and Spawning
Reproductive females develop orange spots on their sides that vary in brightness
depending on the females' ovulation stage. Mating takes place in the spring with
copulation occurring a day or two prior to bright coloration. Eggs hatch about 7-13
weeks after oviposition and growth is rapid.
Diet
Beetles and grasshoppers comprise the majority of the diet, along with arthropods and
small lizards, however, collared lizards are opportunistic feeders and their diets change
based on availability. Juveniles eat small insects and spiders
Biotic interactions
The list of predators includes diurnal raptors and snakes. Although perching in the open
would make them an easy target, collard lizards continue to do so with lack of concern.
4.2 Crotaphytus collaris Collared lizard
4.3 Gambelia wislizeni wislizeni Long-nosed leopard liza rd
Adult/ Juvenile
The leopard lizard can be distinguished by its light brownish-gray body with numerous
small brown spots. Female has red-orange spots that occur on her sides during the
breeding season. Leopard lizard can be found in Oregon, southern Idaho south through
southern and eastern California, Nevada, Utah, western Colorado, Arizona, New Mexico,
and western Texas to northern Mexico.
Leopard Lizards can be most commonly found on sparsely vegetated, flat or gently
sloping shrublands, consisting of greasewood and sagebrush, in or near the mouths of
canyons. Lizards may use rodent or other burrows to seek refuge at nighttime and during
the winter months.
Reproduction
Mating occurs in the spring and eggs are laid underground in their burrows. Hatchlings
appear by the end of the summer and reach maturity in 1-2 yrs.
Diet
Long-nosed leopard lizard diet is dominated by grasshoppers, but also consists of beetles,
spiders, wasps, ant lions, caterpillars, and lizards such as the western whiptail, side-blotched
lizard, and plateau lizard.
Biotic Interactions
Predators include various raptors, carnivorous mammals, and large snakes.
11
Other Common Names: Speckled Earless Lizard, Lesser Earless Lizard
Adult/Juvenile
They are found in southwestern Utah and Colorado, southern South Dakota, eastern
Wyoming south through Nebraska, Kansas, Oklahoma, Arizona, New Mexico, and Texas
to central Mexico. Body 41/2 inches long, short, and somewhat flattened. During
breeding season, reproductive females have an orange-yellow of their throat and sides of
the body. Dry, rocky or sandy areas along streams, and flat areas with sparse vegetation;
lower Sonoran- Transition life zones. The lizard buries itself underground during hot and
cold temperature extremes.
Reproduction
6-8 eggs laid early July -August, hatchlings appear August to September
Diet
Earless lizard is an opportunist, feeding on various small invertebrates such as
grasshoppers, bugs, ants, Lepidoptera, beetles, and spiders.
4.4 Holbrookia maculata approximana ..Speckled Earless lizard
Biotic Interactions
Predators include owls, the long-nosed leopard lizard, hog-nosed snake, racer, bullsnake,
milk snake, western rattlesnake, various hawks and carnivorous mammals, including the
northern grasshopper mouse (Onychomys leucogaster)
4.5 Sauromalus obesus multiforaminatus Glen Canyon chuckwalla
Adult/ Juvenile
Glen Canyon subspecies of chuckwalla is found only in the Colorado River gorge
between Garfield County, Utah and Page County, Arizona. The Glen Canyon
chuckwalla is listed on the species of special concern list due to its population and habitat
decline. It is a rock-dwelling lizard that occurs around the Colorado River from the Glen
Canyon Dam area to near Kite and the Henry Mountains of southeastern Utah.
Characteristics include its thick tail with its blunt tip; it has nasal salt-secreting glands
that are effective in eliminating salts with minimal water loss. This diurnal lizard
emerges in the morning and, before seeking food, basks hi the sun until its optimum body
temperature of 100 ° F. is reached.
Reproduction
Females lay six to ten white soft-shelled eggs during the summer months
Diet
This desert lizard is primarily vegetarian (unlike other reptiles in the region), and eats
fruit, leaves, buds and flowers.
Biotic Interactions
Biotic Interactions are unavailable for this species.
4.6 Sceloporus magister cephaloflavus ....Utah spiny lizard
Adult/ Juvenile
Dorsum with large spiny scales, often scattered yellowish scales on the sides; head
yellowish to orange in adult; male: blue patch at center of the throat, vivid black-edged
blue or green patch on each side of the belly, large black mark on each side of the neck;
females: blue areas faint or absent; found in central California, southern Utah,
southwestern Colorado south through Arizona, New Mexico, and western Texas to
northeastern Baja California and north-central mainland Mexico. Habitat includes shrub-covered
dirt banks and sparsely vegetated rocky areas near flowing streams.
Adults remain in a relatively small home range that is fairly constant year to year in
contrast to juveniles who move several hundred meters before establishing a home range.
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Reproduction
Mating takes place in the spring, clutch size is 2-8 and 2 clutches a year are produced in
southern Utah; hatchlings appear in early Aug in southern Utah and occur most often on
the ground.
Diet
Feed opportunistically on available arthropods, occasional small lizards such as the
western whiptail, and some plant material.
Biotic Interactions
Perch on large rocks, shrubs, or trees such as cottonwoods. They prefer soft soils under
greasewood, rabbit brush, or salt-cedar. Predators include various birds that pluck them
from their perches, collared lizard, and long-nosed leopard lizard.
4.7 Scelopoms undulatus elongatus Northern plateau lizard
Adult/Juvenile
Found in rocky areas throughout eastern Utah, western Colorado, southwestern and
south-central Wyoming, and south into northern Arizona and north-western New Mexico.
Blue patches on sides of throat don't usually meet at midline; lips and chin never orange
or yellow in color, dark crossbands on back often faint, discontinuous or absent, dark
lateral stripe usually present on adult male.
Reproduction
Mating occurs in the spring
Diet
Eats whatever small arthropods are available, ants, beetles and grasshoppers dominate
their diet.
Biotic Interactions
Taxa elongates and tristichus intergrade in southwestern Utah.
4.8 Sceloporus graciosus graciosus Great Basin sagebrush lizard
Adult/Juvenile
Dorsum has small, spiny scales, usually with a pale dorsal-lateral stripe on each side; rear
thigh scales are small, often granular and unkeeled; throat may be blue-mottled, but not
distinct; supra ocular scales separated from median head scales by complete rows of
small scales. Max size is 15cm TL. Distribution: Washington, Idaho, Montana, and
western north Dakota south to northern Baja California, central Arizona, and
northwestern New Mexico. Habitat includes pinon-juniper, semi-desert shrubland
(including saltbush, sagebrush), montane woodlands.
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Reproduction- in So Utah: courtship begins in May ; most females produce 2 clutches/yr
and average 4 eggs, laid in June and July; Hatchlings appear early to mid August.
Survival is 12-66% for egg-to-yearling stage, 40-50% for yearlings, and 40-70% for
adults. In Utah 3A of hatchlings don't survive their first year.
Diet
Ants most important food source, other food includes, grasshoppers, flies, beetles,
spiders, mites and pseudoscorpions.
Biotic Interactions
The sagebrush lizard perches on junipers and other plants, usually near the ground, but up
to heights of 1-2 m. Temp extremes are spent under rocks or in rodent burrows.
Predators include assortment of mammals, birds, and reptiles, noted cases include striped
whipsnake, plateau lizard, American kestrels, and ash-throated flycatcher.
4.9 Ufa stansburiana stansburiana Northern side-blotched lizard
Adult/Juvenile
Dorsum uniform color or w/ numerous small light and dark dots, scales along the middle
of back are uniform size; dark blotch on the sides of chest, throat often blue with orange
rim; a large % of adults have either broken or regenerated tails. Distribution: south-central
Washington, southeastern Idaho, western Colorado, southwestern Oklahoma,
south through Oregon, California, Nevada, Arizona, New Mexico, and Texas to southern
Baja California, and northwestern and north-central mainland Mexico. Abundance
increases with amt of precipitation from previous year.
It's found in washes, boulder-strewn ravines, rocky canyon slopes, bedrock exposures,
rimrock outcroppings, rocky cliff bases, and flat, shrubby areas in canyon bottoms with
soft, deep soils. Open pinon-juniper, semidesert shrubland, patchy stream-side
vegetation. Burrow underground in winter.
Reproduction
Courtship begins in the spring following the emergence form hibernation; females may
store and use sperm for up to several months after mating. One clutch/season, hatchlings
emerge in August.
Diet
Opportunistic foragers; include grasshoppers, beetles, leafhoppers, and other bugs, ants,
various insect larvae, and spiders. Cannibalism occasionally occurs (noted that adult
males had eaten juveniles).
Biotic Interactions
Predators include striped whipsnake and especially the leopard lizard, also potential from
reptiles, birds, mammals, and invertebrates such as spiders and scorpions.
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4.10 Phrynosoma douglassi hernandesi... Mountain short-horned lizard
Adult/Juvenile
Body wide and flattened, spines at back of the head are the same length as width at the
base, one row of enlarged scales fringing each side of the body. Dorsal color orientation
blends cryptically with soil. 30-33mm TL in Utah; distribution: southern Alberta and
Saskatchewan south through Montana, Wyoming, the western Dakotas, eastern Nevada,
Utah, Colorado, western Nebraska, Arizona, New Mexico, and western Texas to south-central
Mexico. Habitat varies from short-grass prairie, sagebrush, semidesert shrubland,
shale barrens, pinon-juniper, pine-oak, oak-grass, open conifer forests. Note: movement
patterns poorly known, but in Utah a juvenile displaced 400m from its capture location
returned to that site after 280 days.
Reproduction
Mating in the spring, some females may be unreceptive to males after mating, others
mate more than once in a few-day period. This species does not lay eggs, rather it gives
birth to live young (eggs develop inside the female during spring and summer -gestation
is about 3 months). Neonates quickly shed their sacs and begin feeding after 1-2 hrs from
birth.
Diet
Ants dominate the diet, also eat miscellaneous other insects and spiders, also beetles and
small grasshoppers.
Biotic Interactions
Little predation info avail; striped whipsnake and burrowing owl
4.11 Xantusia vigilis utahensis Utah night lizard
Adult/Juvenile
The Utah night lizard is listed as a species of special concern due to its specialized habitat
within the Glen Canyon region. It occurs under and among rocks or fallen plant material
(e.g. yucca) from Henry Mountains and Natural Bridges National Monument (east of the
Colorado River) south to the San Juan River. The Utah Night lizard has lidless eyes and
vertical pupils.
Reproduction
Night lizards give birth to live young. They mate in early summer, usually May or June,
and 1 to 3 young are born, tail first, a few months later.
Diet
It frequents yucca plants and agaves and feeds on termites, ants, beetles and flies, which
it finds among vegetation or rocks.
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Biotic Interactions
Biotic Interactions are unavailable for this species.
4.12 Cnemidophorus tigris septentrionalis Western whiptail
Adult/Juvenile
Body long and slender, dorsum with small granular scales, belly with larger rectangular
scales, unmarked or with black marks on the front edge of some; dorsum with light
stripes, dark fields broken into separate bars or spots; throat may be pinkish or orangish
in adults; distribution: eastern Oregon and southern Idaho, south through California,
Nevada, Utah, western Colorado, Arizona and New Mexico, and western Texas to
southern Baja California and northwestern and north-central Mexico.
Larger individuals spend more time in the shade than juveniles despite similar thermal
preferences and tolerances.
Lowland river valleys, canyon bottoms to adjacent low mesa tops; openly spaced shrubs
(greasewood, sagebrush, rabbit brush) or pinon pine; areas along rivers with patchy
shrubs and scattered cottonwood trees; winter spent in rodent or self-dug burrows.
Reproduction
Mating from late May to mid June; male and female form temporary monogamous pairs;
hatchlings appear in September; clutch size and growth rates increase with arthropod
abundance associated with higher precipitation levels
Diet
They feed opportunistically on arthropods, specifically those found in plant litter at the
base of perennial plants. Probe leaf litter and climb into plants to get prey. Odors sensed
by the tongue help reveal potential prey. Diet includes beetles, grasshoppers, insect
larvae, termites, ants, and sometimes scorpions and side-blotched lizards. Also predation
on small Sceloporus lizards.
Biotic Interactions
Predators include roadrunners, hawks, collared lizards, leopard lizards, whip snakes, and
racers, long-nosed leopard lizard.
4.13 Cnemidophorus sacki innotatus Plateau whiptail
Adult/ Juvenile
Body long and slender, dorsum with small granular scales, belly with large rectangular
scales, dorsum and sides with six or seven light stripes, dark fields between the stripes are
interrupted by light areas; tail blue (pale in adult; bright in juvenile)
Distribution: southern Utah, western Colorado, northern and central Arizona, and
northern and central New Mexico.
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Habitat includes pinon juniper, sagebrush, semi-desert and mountain shrublands, lowland
riparian zones, encompassing rocky slopes and deep sandy soils in flat areas. Ground-dwelling.
Reproduction
Species consists only of females and reproduces by parthenogenesis. Eggs are laid
around June and hatchlings appear mid- to late August.
Diet
Opportunistic feeders -arthropods found on the ground or shallowly buried; includes
spiders, caterpillars, grasshoppers, crickets, adult and larval beetles, aphids, leafhoppers
and other insects; ants eaten infrequently;
Biotic interactions: predators include various birds, reptiles, and mammals
4.14 Thamnophis cyrtopsis cyrtopsis Western black-necked garter snake
Adult/Juvenile
Aquatic snake; Sees well in the air, but poor underwater vision; moderately fragile tail
that breaks between rather within the vertebrae and doesn't significantly regenerate.
Biotic interactions
Prey on amphibians in temporary pools in both lowland and upland areas; native stream
associated spp include red-spotted toad, plains leopard frog, black-necked garter snake,
and plains garter snake. Black-necked garter snake sometimes preys on Woodhouse
toads. Garters are preyed upon by racers
4.15 Thamnophis elegans vagrani Wandering garter snake
Adult/Juvenile
Aquatic snake; Sees well in the air, but poor underwater vision; moderately fragile tail
that breaks between rather within the vertebrae and doesn't significantly regenerate.
Biotic interactions
Prey on amphibians in temporary pools in both lowland and upland areas; native stream
associated spp include red-spotted toad, plains leopard frog, black-necked garter snake,
and plains garter snake.
5.0 Summary
Several factors have contributed to the decline of amphibian and reptile species diversity
and population size. By far, Glen Canyon Dam has created a large impact in the habitat
and species associated. All of the species listed in this report currently rely on Glen
Canyon and its surrounding habitat for their survival. It is critical to continue to monitor
these species as indicators of the health of this remarkable area.
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6.0 Literature Cited
Bernard, Stephen R. and Kenneth R. Brown. U.S. Department of the Interior - Bureau of
Land Management Technical Note. "Distribution of Mammals, Reptiles, and
Amphibians by BLM Physiographic Regions and A.W. Keuchler's Associations
for the Eleven Western States." Issued August 1977, Revised July 1978.
Collins, Henry Hill, Jr. Complete Field Guide to American Wildlife. New York: Harper
& Brothers Publishers, 1959.
Hammerson, Geoffrey A. Amphibians and Reptiles Field Guide, Second Edition. Niwot,
Colorado: University Press of Colorado & Colorado Division of Wildlife, 1999.
Tanner, Wilmer W. "1975 Checklist of Utah Amphibians and Reptiles." Provo, Utah:
Brigham Young University, 1975.
University of Utah, "Endemic Amphibians and Reptiles of the Colorado River System: A
Status Report."
Utah Division of Wildlife Resources. Amphibian and Reptile Distribution Maps,
Latilong Distribution, 1979.
Woodbury, Angus M. and the staff of the Division of Biological Sciences. Working Plan
for Ecological Studies as Part of the Upper Colorado Basin Salvage Program.
National Park Service and University of Utah, 1957.
Woodbury, Angus M. University of Utah Anthropological Papers. "Ecological Studies
of the Flora and Fauna in Glen Canyon." University of Utah Press, 1959.
Woodbury, Angus M. University of Utah Biological Series, Volume 1 Number 4. "A
Descriptive Catalog of the Reptiles of Utah." University of Utah Press, 1958.
Woodbury, Angus M. University of Utah Biological Series, Volume 1 Number 31.
"Biological Resources of Glen Canyon Reservoir." University of Utah Press,
1958.
Woodbury, Angus M. Working Plan for Ecological Studies. University of Utah Press,
1957.
World Wide Web, Accessed Division of Fish and Wildlife, Department of Natural
Resources, Bureau of Land Management, and National Park Service websites,
2000.
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